Raster is a data format consisting of regular grids of values, usually stored in an image-like format.

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87 views

How to visualize the water equivalent between two raster layers in arcmap 10.1?

I do have two raster layers (interpolated with Empirical Bayesian Kriging), that show the elevation of a glacier in April, and September. I want to show the change in elevation between the layers in ...
4
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1answer
157 views

Why does the added raster layer have strange edges?

I'm using Geoserver in conjunction with the google maps API to add a raster layer onto a map. It loads fine, however there's some strange problem with opacity at the edge of the layer where you can ...
3
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1answer
758 views

Importing grib, grib2, netcdf to PostGIS

According to grib2 to raster? (grib2 -> raster2pgsql -> PostGIS 2.0 -> GeoServer), it seems like that grib2 can be treated as raster directly. Is it the so called "standard" way? How about ...
2
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2answers
557 views

ArcPad Raster Not Displaying Correctly?

I have a hillshade that I would like to use as a background in an ArcPad 10 map. I get everything set how I want in in ArcMap and when I export the map to use on my Trimble the hillshade doesn't show ...
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1answer
164 views

cannot print listRasters

I'm trying to run this very simple script to check a problem in another more comlpex one. import arcpy arcpy.env.workspace= 'C:\\Users\\Umberto\\Desktop\\Prove_Script\\Karakoram\\temporary_01' rst= ...
5
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2answers
1k views

How to extract values from a raster according to Lat and long of the values?

having 12 files with 12 hdrs for one year: these files are raster (projected WGS84,lat long): samples = 1440 lines = 720 bands = 1 header offset = 0 ...
4
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3answers
190 views

Where can I find decadal climate and ocean data for Europe?

I would like to find 'decadal' climate and ocean data for Europe that I can download and use directly in ArcGIS? Specifically, I am looking for mean annual temperature, sea surface temperature, and ...
5
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1answer
105 views

What GIS software is required to export a GIS map as a hi-res raster image?

I am looking for some (preferably free) GIS software that will enable me to export multi-layered world maps (made up of shape-files and kml files and so on) as hi resolution (21,000 pixels wide), ...
1
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1answer
309 views

How to add multiple rasters to a layer file?

I'm trying to make a .lyr file to bring into ArcMap with arcpy.mapping. I can bring a single raster into a .lyr with the script below. I'm unsure how to proceed to get multiple rasters from the same ...
2
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3answers
4k views

How to georereference a TIFF file which has already a spatial reference?

I have a TIFF file of Poland and a self drawn vector map of Poland. The vector map has no spatial information. I am intending to reference the TIFF exactly to the shape of the self drawn map. My ...
4
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1answer
259 views

Use csv file as raster file and stitch them together

I'm having an issue trying to stitch together 100 32bit Tiff files (coming from thermal imagery video and extracted as 32bit Tiff). I used Hugin to mosaic the pictures extracted from the video which ...
3
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1answer
300 views

shortest distance between a raster and another raster

i am using arcgis 10.1 i want to calculate the shortest distance between a raster and another raster. i have a bathymetric raster and an underlying fault plane raster. for each bathy raster cell, i ...
4
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1answer
302 views

How can I avoid reprojection gaps when merging DEM rasters?

I have two raster DEMs in same resolution I want to bring together. I was using the merge-function in SAGA, GRASS and QGIS but I always get the following result: What do I need? Where could the ...
1
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3answers
3k views

QGIS Raster Calculater Syntax

I am trying to use the raster calculator in QGIS to combine a number of rasters. I want to calculate a mean, this is easy: (raster_1@1 + raster_2@1 + raster_3@1) / 3 I then want to create a max. ...
6
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1answer
233 views

Add raster paths to shapefile with Python (ArcGIS)?

I have a problem and maybe someone is able to help me or give me some hints how to start. Situation: I have a lot of raster and of every raster I have the center coordinate. Out of this coordinate I ...
2
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1answer
847 views

Output of QGIS raster clipper not as expected?

My goal is to clip a raster with a polygon in QGIS 1.8. Based on an article I read, this should be a pretty straightforward task. However, the output appears to be empty. The raster produced is the ...
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0answers
471 views

Raster calculator error 000539 - cannot create weak reference to 'classobj' object

I was - like many times before - trying to clip a raster with the raster calculator (raster * 1 with shapefiles as mask). Now - the following error keeps popping up: ERROR 000539: Error running ...
3
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1answer
84 views

Get rid of raster grid cells that are less than 1

I'm using QGIS to work with raster data. I have a raster dataset of a country where each grid cell is assigned a number 1-100. However, the raster is in the format of a rectangle based on the extent ...
6
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1answer
369 views

How to reclassify raster data by their sign?

I want to do the following: I have two data raster sets with different units and values. One results from measured metric data, the other from modelled grid values. What I want to compare is simply ...
3
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0answers
110 views

Geoserver Raster layer cropped by polygon?

I've got a Geoserver raster layer which represents a satellite image. I use the Geoserver WMS to display the raster in OpenLayers. I want to display only parts of the raster - those within a certain ...
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0answers
1k views

How to resample a raster in QGIS?

I've got a boundary file that I would like to resample the raster file from a 30m grid to a 10m grid inside the boundary file. When I try and do it in Qgis or Grass all I get is one big raster cube ...
8
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2answers
615 views

How to create a solar intensity map for a garden plot?

I'm interested in creating a raster surface that depicts the average solar intensity per unit area for a small garden plot. I imagine the inputs into the model would be the following: Plot ...
10
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2answers
3k views

Aggregating points to grid using R

I have a question with regard to spatial aggregation in R. What I am trying to do is aggregate a point dataset to a grid. I am unsure however how to do this as I have little experience with this sort ...
2
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1answer
400 views

How do I create rendered vector field in qgis

Perhaps I am misunderstanding the "vector field renderer" and "VectFieldCalc" plugins, but I have no idea how to make a vector field of arrows, with directions and magnitude. I have the data loaded ...
7
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2answers
1k views

Extracting roads out of Landsat raster images

For a study into the expansion of road networks in the rainforest I am trying to extract roads out of Landsat images. We already have sharp and cloud-free composites on which the roads are clearly ...
3
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1answer
583 views

Build Raster Attribute Table with GDAL Utilities

Is there a way to build a raster attribute table using one of the GDAL utilities? I know you can view it using gdalinfo and I have successfully created one using Python, but it would be so much ...
2
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1answer
136 views

Are there any open source distribution raster merging functions within JTS or GeoTools

I'm looking for something similar to the combine function from the ISelectionSet interface from ArcObject's SDK 10 .NET framework on a more scaled down level. Ergo, I don't plan on using that ...
1
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1answer
126 views

Set certain amount of pixels to 1 inside of a polygon (GRASS)

I have a rather coarse vector map with polygons and want to calculate a (sufficiently) finer raster map defined by spatial extension and resolution. Every polygon of the vector map has a value ...
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3answers
157 views

Applying rotation before FeatureToRaster_conversion?

I am converting polygon shapefiles to rasters. With arcpy I am using the function FeatureToRaster_conversion. gp.FeatureToRaster_conversion(InFeatures, InField, OutRaster, InCellSize) This function ...
2
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0answers
158 views

Plot the Shortest Paths in a Grid without any clash at a point of time

The efficient algorithm needs to be done and proved for the best solution for the given problem: User inputs: (#) Size of the NxN Grid. (N); (#) No. of Paths: Z; (#) Source and Destination ...
2
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1answer
348 views

Saving rasters in a Python for loop fails only on last iteration

I'm a newcomer to Python scripting and I'm having what's seemingly a very simple problem but one that's stumped me enough to send me posting to these forums for the first time. I'm using a for loop ...
5
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1answer
3k views

Reassigning raster cell values from another attribute in raster attribute table?

I have a large (size of lower 48 U.S.) 100m resolution raster dataset that has a raster attribute table (RAT). The data were created by someone else. One of the attributes in the RAT has the data ...
2
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1answer
406 views

USGS GeoTiff extent via GDAL

I have 2006 land cover GeoTiff from the USGS site (for a county in VA, USA). The projection is Albers Conical Equal Area Units. The download came with an HTML metadata file that tells me the geo ...
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0answers
135 views

jagged edges in mosaic DEM

I encounter edge issues when trying to mosaic USGS NED DEMs in ArcGIS 10.0.0. After projection and aggregation, I attempt arcpy.MosaicToNewRaster_management(). I've reproduced the same results using ...
5
votes
1answer
227 views

parallelization of raster mosaic

I would like to create a raster mosaic of the national USGS NED 30m DEM (~50 GB). I'd like to leverage parallel processing using python multiprocessing module where possible. I'm using ArcGIS 10.0. My ...
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0answers
35 views

I need advice in using QGIS Lisboa 1.8 (vol 2) [duplicate]

Possible Duplicate: I need a advice in using QGIS lisboa 1.8(vol 3) My previous question was not clear, so again my question is: In an urban area with polygon and dots, how could I display ...
11
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2answers
540 views

Converting ascii windspeed files to rasters

I have been trying to convert windspeed files to rasters without success. It was discussed in an Arcgis forum which I followed. This involved replacing semi-colons with spaces and adding a header. I ...
5
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1answer
178 views

GDAL/OGR Determine if dataset is raster or vector

I am writing a script using the GDAL/OGR Python bindings and it is possible that the user may provide a raster dataset or a vector dataset as input. If the user provides a vector dataset, the script ...
3
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3answers
3k views

How to subset raster image using gdal?

I have read pixel values of an raster image using GDAL libraries in visual studio 2010(vc++). Now I have to crop the image (subset) according to the grid given in shape file. I have got a code for ...
3
votes
1answer
361 views

An error in raster calculator in Arcgis

I wrote and ran this formula in raster calculator in ARCGIS. But the following error gets me into trouble. Does anyone have a suggestion to overcome this? Here is the formula I wrote and the error ...
2
votes
1answer
218 views

ArcObject 10.1 Java : Raster Analysis

I have been working with ArcObjects Java for a short time and have not been able to find a solution to the following problems: How to get the Raster object from a IRaster reference? IRaster raster = ...
0
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2answers
2k views

Difference between Geostatistical Analyst and Spatial Analyst toolboxes for interpolation?

I did interpolation on point data using "Geostatistical Analyst" tool. It gives me surface layer. Then I exported this layer into raster image (by right click on this layer=>export data into raster) ...
2
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1answer
629 views

Managing sizes of input rasters for raster calculation in ArcGIS Desktop?

To calculate any formula (conditional statements/relational operation etc) in the raster calculator in ArcGIS using two different sources of raster images, I'd like to know input rasters must be the ...
3
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0answers
308 views

Getting coordinates of pixels

I want to compute an area of certain object on a picture using Monte Carlo method. The picture shows some shape on white background. To do so I figured out that I'd get the coordinates of non-white ...
4
votes
1answer
174 views

How to stack rasters for ecological analysis?

The attached image shows two different forest openings. Each opening has the following layers associated with it: Point shapefile 1 = A red X which represent a large "legacy" tree in the gap Point ...
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6answers
1k views

Finding minimum bounding extent of given pixel value within raster?

I am wondering if there is a way to find the minimum bounding extent for a raster with a particular value. I clipped a raster from a global image and the extent is set as the global extent with a lot ...
9
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2answers
3k views

How to reclassify a very large land cover dataset?

Consider the NLCD2001 Land Cover dataset for Alaska (download link). I need to reclassify this dataset so that only pixels of value 41, 42, and 43 are preserved; all other pixel values should become ...
14
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3answers
417 views

Is it possible to use symbols instead of colours to visualise raster cell values?

I have a raster image (GeoTIFF) with integer values. I know how to visualise raster values in QGIS using colormaps or similar, but I would like to assign symbols to each colour value instead - just ...
7
votes
2answers
777 views

How to perform enhancement operations on an satellite imagery in QGIS?

I am a new user of QGIS please suggest how to perform image enhancement operations on an satellite imagery like ratioing, contrast stretching, edge engancement, filtering etc. in QGIS?
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0answers
227 views

How to rename .met file with model builder which uses an iterator to rename .sid files?

I have a model that iterates through a folder containing .sid raster datasets, amongst other types of rasters (so I'm using a *.sid wildcard). I note, however, that ArcCatalog/Model Builder/Rename ...